kernel: preemptive and cooperative scheduler refactoring.

[bertos.git] / bertos / kern / preempt.c

diff --git a/bertos/kern/preempt.c b/bertos/kern/preempt.c
index 7ecd481d0cdf57c6d4c3679fc4ccfa43f5cc794e..078724b42a8e38095fb93e3c6e226d2e2b5e2d70 100644 (file)
--- a/bertos/kern/preempt.c
+++ b/bertos/kern/preempt.c
@@ -26,152 +26,7 @@
  * invalidate any other reasons why the executable file might be covered by
  * the GNU General Public License.
  *
- * Copyright 2008 Bernie Innocenti <bernie@codewiz.org>
- * -->
- *
- * \brief Simple preemptive multitasking scheduler.
- *
- * \version $Id: proc.c 1616 2008-08-10 19:41:26Z bernie $
- * \author Bernie Innocenti <bernie@codewiz.org>
- */
-
-#include "proc_p.h"
-#include "proc.h"
-
-#include <kern/irq.h>
-#include <kern/monitor.h>
-#include <cpu/frame.h> // CPU_IDLE
-#include <drv/timer.h>
-#include <cfg/module.h>
-
-
-
-Timer preempt_timer;
-
-/**
- * Disable preemptive task switching.
- *
- * The scheduler maintains a per-process nesting counter.  Task switching is
- * effectively re-enabled only when the number of calls to proc_permit()
- * matches the number of calls to proc_forbid().
- *
- * Calling functions that could sleep while task switching is disabled
- * is dangerous, although supported.  Preemptive task switching is
- * resumed while the process is sleeping and disabled again as soon as
- * it wakes up again.
+ * \note This file is deprecated and kept only for backward compatibility.
  *
- * \sa proc_permit()
- */
-void proc_forbid(void)
-{
-       /* No need to protect against interrupts here. */
-       ++CurrentProcess->forbid_cnt;
-}
-
-/**
- * Re-enable preemptive task switching.
- *
- * \sa proc_forbid()
- */
-void proc_permit(void)
-{
-       /* No need to protect against interrupts here. */
-       --CurrentProcess->forbid_cnt;
-}
-
-
-void proc_preempt(void)
-{
-       IRQ_DISABLE;
-
-       LIST_ASSERT_VALID(&ProcReadyList);
-       CurrentProcess = (struct Process *)list_remHead(&ProcReadyList);
-       LIST_ASSERT_VALID(&ProcReadyList);
-       ASSERT2(CurrentProcess, "no idle proc?");
-
-       IRQ_ENABLE;
-
-       TRACEMSG("new proc: %p:%s", CurrentProcess, CurrentProcess ? CurrentProcess->monitor.name : "---");
-       monitor_report();
-}
-
-void proc_preempt_timer(UNUSED_ARG(void *, param))
-{
-       IRQ_DISABLE;
-/*
-       if (!CurrentProcess->forbid_cnt)
-       {
-               TRACEMSG("preempting %p:%s", CurrentProcess, CurrentProcess->monitor.name);
-               LIST_ASSERT_VALID(&ProcReadyList);
-               SCHED_ENQUEUE(CurrentProcess);
-               proc_preempt();
-       }
-*/
-       IRQ_ENABLE;
-
-       timer_setDelay(&preempt_timer, CONFIG_KERN_QUANTUM);
-       timer_add(&preempt_timer);
-}
-
-void proc_schedule(void)
-{
-       TRACE;
-
-       // Will invoke proc_preempt() in interrupt context
-       kill(0, SIGUSR1);
-}
-
-void proc_yield(void)
-{
-       TRACE;
-
-       ASSERT_IRQ_ENABLED();
-       IRQ_DISABLE;
-       SCHED_ENQUEUE(CurrentProcess);
-       LIST_ASSERT_VALID(&ProcReadyList);
-       proc_schedule();
-       IRQ_ENABLE;
-}
-
-void proc_entry(void (*user_entry)(void))
-{
-       user_entry();
-       proc_exit();
-}
-
-
-static cpustack_t idle_stack[CONFIG_PROC_DEFSTACKSIZE / sizeof(cpustack_t)];
-
-/*
- * The idle process
- *
- * This process never dies and never sleeps.  It's also quite apathic
- * and a bit antisocial.
- *
- * Having an idle process costs some stack space, but simplifies the
- * interrupt-driven preemption logic because there is always a user
- * context to which we can return.
+ * -->
  */
-static NORETURN void idle(void)
-{
-       for (;;)
-       {
-               TRACE;
-               monitor_report();
-               proc_yield(); // FIXME: CPU_IDLE
-       }
-}
-
-void preempt_init(void)
-{
-       MOD_CHECK(irq);
-       MOD_CHECK(timer);
-
-       irq_register(SIGUSR1, proc_preempt);
-
-       timer_setSoftint(&preempt_timer, proc_preempt_timer, NULL);
-       timer_setDelay(&preempt_timer, CONFIG_KERN_QUANTUM);
-       timer_add(&preempt_timer);
-
-       proc_new(idle, NULL, sizeof(idle_stack), idle_stack);
-}